1. Field of the Invention
The present invention relates to a device for indicating that an attempt has been made to tamper with a locking or security seal. More particularly, the present invention relates to a device for visually indicating that someone has tampered with or attempted to defeat a locking or security seal on an ocean container, truck trailer, freight car, equipment cabinet, switch or other item which is intended to be, and to remain, secure.
2. Prior Art
Locking or security seals are used to nominally prevent tampering with, pilferage from, and unauthorized entry to or operation of various items. Such seals are also intended to provide an indication that an unauthorized attempt, successful or otherwise, has been made to enter or operate an item by tampering with or defeating the seal.
The doors of ocean containers, truck trailers, freight cars and equipment cabinets, as well as items such as railway switches and high-voltage switches are often secured with a locking or security seal.
Typical seals include a metal male member, which may be a headed rigid bolt, or a flexible cable with a head at one end and a solid tip on the other end, and a metal female member or lock body for receiving the unheaded end of the bolt or the tip of the cable in a passageway thereof. Once the bolt end or tip end is inserted into the passageway, it is retained and restrained therein by appropriate facilities. These facilities may include a circumferential groove near the end of the bolt or tip and a circumferential groove in the wall of the passageway. A locking ring, C-ring or spring ring within the passageway surrounds the bolt or tip end and partially occupies the groove in the bolt or tip as well as the groove in the passageway to interfere with, and prevent, removal of the bolt or cable from the lock body. Other facilities for preventing removal of the bolt from the lock body may include spring-loaded fingers extending into the passageway and engaging notches in the bolt or tip.
Typical locking or security seals are shown and described in the following United States Patents, all but the last being commonly assigned with the present invention: U.S. Pat. Nos. 3,980,337; 4,152,909; 4,193,276; 4,326,740; 4,802,700; and 4,280,726.
To secure a door or other item, the bolt or cable may be inserted through an aperture in a latch, staple, hasp or other locking member in such a way as to interfere with opening, unlocking or operational movement thereof. Thereafter, the bolt or tip is inserted into and retained in the lock body as described above. A padlock or other locking device may be used in conjunction with the locking seal.
A locking or security seal will usually prevent opening of a door or other item when an interloper attempting same is an unsophisticated interloper, such as a vandal, casual thief or other person who does not possess a bolt cutter or other device for cutting the bolt or cable and/or breaking or removing the locking device, if one is used. However, sophisticated interlopers, such as professional thieves and others who possess appropriate tools like bolt cutters, may gain entry simply by cutting the bolt or cable of the seal (and the locking device where one is used). At times the sophisticated interloper may "reassemble" the cut seal by repositioning its now non-integral parts in such a way as to make it appear that defeat thereof and unauthorized entry or operation have not occurred. Another sophisticated approach may involve gross disintegration of one or more parts of the seal followed by replacement thereof with counterfeit parts associated together to mimic an integral, untampered seal.
The sophisticated interloper may also attempt to defeat the locking seal by inserting a shim or the like into the passageway between the end of the bolt or tip and the lock body to remove the ring or the fingers, therewithin from one of the circumferential grooves or notches, thus permitting removal or the bolt or tip end from the lock body. Following unauthorized entry, the locking seal may be reassembled to hide the fact of its defeat.
Thus, a locking or security seal is a physical deterrent, nominal or real, to unauthorized entry or operation in the same manner as a lock. It also serves as a psychological deterrent: interlopers may eschew attempting unauthorized entry which they known will be detected through later visual observation of the breaking of, or tampering-indicating marks on the metal parts of, the seal.
As noted, however, the seal may not successfully deter, physically, psychologically or otherwise, the professional thief or other sophisticated interloper who has the capacity to defeat the seal and to gain unauthorized entry or effect unauthorized operation. Where defeat of the seal is achieved by cutting or other gross disintegration thereof, or where a shim or similar device has been used, a clear indication of tampering is given, unless a successful apparent or actual reassembly has been effected with the original seal's elements or with counterfeits thereof.
It is often desirable to detect unsuccessful attempts to tamper with or defeat a locking or security seal. For example, if there occur numerous or repeated attempts to gain unauthorized entry or to effect unauthorized operations at a specific location, detection of these attempts permits security or surveillance in such locations to be increased or improved so that the interlopers may be apprehended before they achieve their goal.
It is also desirable to detect successful attempts to tamper with or defeat a seal. Those successful attempts that are not accompanied by apparent or actual reassembly of the seal (or of counterfeit portions thereof), are easily visually detectable by observation of the non-integral seal.
Successful attempts at seal defeat followed by reassembly of the original seal (or its counterfeit) and failure to detect such reassembly are insidious. A theft following defeat of the seal may go undetected for some time, which may prevent identification of the location of the theft and render difficult apprehension of the perpetrators. Even more troublesome is the undetected placement of contraband, such as illicit narcotics, in an otherwise proper shipment of cargo. Moreover, undetected and unauthorized operation of an item following defeat of the seal may lead to untoward events caused by incorrect assumptions concerning the condition of the affected item. For example, an undetected change in the condition of an electrical or railway switch can lead to a catastrophic event.
Due to an unsuccessful attempt to defeat the seal or a successful attempt followed by reassembly of the seal (or its counterfeit), the metal lock body or the metal bolt or cable may bear marks, gouges or nicks giving visual evidence of the attempt. However, such marks may not be easily detected or may be overlooked. Also, the use of non-abrading or protective materials, such as rags or rubber sheets, in conjunction with grasping or holding tools used to defeat the seal may obviate or ameliorate such marks. Further, replacement and apparent reassembly of a defeated seal via the use of unmarked counterfeit parts may go undetected.
An object of the present invention is the provision of a device which will provide a visual indication of an attempt, successful or unsuccessful, to defeat a locking or security seal. The device of the present invention provides this indication regardless of the care used in attempting such defeat, regardless of the techniques employed, and regardless of successful reassembly or counterfeitting of a defeated seal.